president obama said, "i am president obama and i approve this message." this is someone who wants to get attention. it is important to note that both are getting letters right now, republicans and democrats. that says to me this is someone who really hates government. the u.s. -- in the u.s., antigovernment extremists have a fascination with ricin in the past. you can easily buy manuals on how to produce ricin. >> from what you are hearing is there -- hearing, is there any indication that there might be a link between the ricin in these letters and the bombing in boston? >> not yet eerie -- not yet. >> thank you very much. >> back on this side of the atlantic, former british prime minister margaret thatcher has been laid to rest in a ceremony at st. paul's cathedral pier g was a divisive figure -- st. paul's cathedral. she was a divisive figure. she ushered in policies that continue to impact the country. >> thing then was silent as the first female and longest -- big ben was silent as the first female and longest-serving prime minister was laid to rest.